19984409 has 4 divisors (see below), whose sum is σ = 21036240. Its totient is φ = 18932580.

The previous prime is 19984381. The next prime is 19984417. The reversal of 19984409 is 90448991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90448991 = 2707 ⋅33413.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19984409 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19984409.

It is not an unprimeable number, because it can be changed into a prime (19984109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 525887 + ... + 525924.

It is an arithmetic number, because the mean of its divisors is an integer number (5259060).

Almost surely, 2^19984409 is an apocalyptic number.

19984409 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

19984409 is a deficient number, since it is larger than the sum of its proper divisors (1051831).

19984409 is a wasteful number, since it uses less digits than its factorization.

19984409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1051830.

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 19984409 is about 4470.3924883616. The cubic root of 19984409 is about 271.3712091815.

The spelling of 19984409 in words is "nineteen million, nine hundred eighty-four thousand, four hundred nine".